JP2001168385A - Iii nitride compound semiconductor element and iii nitride compound semiconductor light emitting element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a III nitride semiconductor light emitting element having a clad layer in which an elastic constant is lowered. SOLUTION: The clad layer is formed in a multilayer structure obtained by laminating 20 respective layers of an Al0.2Ga0.8N having a thickness of 50 nm and a Ga0.99In0.01N having a thickness of 20 nm. Since the clad layer of about 1.4 μm has the multilayer structure, its elastic constant is low due to the multilayer structure. A laser diode is useful by forming a guide layer or the like such as the other layer needing a band gap of a gallium aluminum nitride (AlxGa1-xN, 0<x<1) of a multilayer structure of the gallium aluminum nitride (AlxGa1-xN, 0<x<1) and an indium gallium nitride (GayIn1-yN, 0<y<1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a group III nitride compound semiconductor device. The present invention relates to a light emitting diode (LE
Functions as a light emitting element such as D) or laser diode (LD)
It is particularly useful for group III nitride compound semiconductor devices.
Incidentally, the group III nitride compound semiconductor is, for example, AlN, Ga
Binary systems like N, InN, Al _x Ga _1-x N, Al _x In _1-x N, Ga _x In
_A ternary system such as _1-x N (both 0 <x <1), Al _x Ga _y In
_1-xy N (0 <x <1, 0 <y <1, 0 <x + y <1) General formula Al _x Ga _y In _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x
+ y ≦ 1). In the present specification, unless otherwise specified, a group III nitride-based compound semiconductor simply referred to as a group III nitride-based compound semiconductor is a group III nitride-based compound semiconductor doped with an impurity for changing the conductivity type to p-type or n-type. Is also included.

[0002]

2. Description of the Related Art A group III nitride compound semiconductor is a direct transition type semiconductor having an emission spectrum ranging from ultraviolet to red over a wide range, such as a light emitting diode (LED) or a laser diode.
(LD) and the like. In this group III nitride compound semiconductor, sapphire is usually used as a substrate and is formed thereon. At this time, a so-called cladding layer is provided so that electrons from the negative electrode and holes from the positive electrode generate pairs in the light emitting layer. In a group III nitride compound semiconductor light emitting device, it is common to use Al _x Ga ₁ -xN (0 <x <1) containing aluminum (Al) as a cladding layer.

FIG. 3 shows the structure of a light emitting diode (LED) 900 as an example of a conventional group III nitride compound semiconductor light emitting device. The light emitting diode (LED) 900 has a sapphire substrate 901 and the sapphire substrate 90.
1, an AlN buffer layer 902 is formed.

On the buffer layer 902, an n layer 903 made of silicon (Si) doped GaN and a silicon (S
i) doped Al _x Ga consisting _1-x N n-cladding layer 904, Ga _y In
An active layer 905 having a multiple quantum well structure (MQW) in which well layers made of _1-yN and barrier layers made of GaN are alternately stacked. Then, on the active layer 905, a p-cladding layer 9 made of magnesium (Mg) doped Al _x Ga ₁ -xN
06, a p-contact layer 907 made of magnesium (Mg) -doped GaN is formed. Then, an electrode 908A is formed on the p-contact layer 907. Also, the n layer 9
An electrode 908B is formed on the substrate 03.

[0005]

However, in the above prior art, since the elastic constants of the n and p cladding layers made of thick Al _x Ga ₁ -xN (0 <x <1) are high, the n and p cladding layers are thick. Cracks are likely to occur, resulting in poor element characteristics.

Accordingly, the present invention has a low elastic constant and a large elastic constant.
It is an object of the present invention to provide a group III nitride-based compound semiconductor device and a group III nitride-based compound semiconductor light-emitting device that do not deteriorate the function of the Al _x Ga _1-x N (0 <x <1) layer as a device.

[0007]

According to the first aspect of the present invention, there is provided a group III nitride compound semiconductor device comprising an Al _x Ga ₁ -xN (0 <x <1 a), Ga _y I
It is characterized by having three or more layers each of n _1−y N (0 <y <1).

According to a second aspect of the present invention, in the group III nitride-based compound semiconductor device according to the first aspect, the thickness of the layer comprising Ga _y In _1-y N (0 <y <1) is reduced. Thickness is more than 15nm
It is characterized by being 30 nm or less.

According to a third aspect of the present invention, there is provided a group III nitride compound semiconductor light emitting device using the group III nitride compound semiconductor device according to the first or second aspect as a light emitting device. .

[0010]

In the group III nitride-based compound semiconductor device, a layer requiring a wide band gap is Al.
_x Ga _1−x N (0 <x <1) is obtained. Then Al _x Ga _1-x N (0
<By forming a multilayer structure with x <1) and _{Ga y In 1-y N (} 0 <y <1), Al x Ga 1-x N (0 has a wide bandgap <x <1) In addition, a layer having a small elastic constant as a whole can be obtained. Therefore, it is possible to suppress the occurrence of cracks due to a temperature change or the like during manufacturing or use (claim 1). this is
Al _x Ga _1-x N is particularly pronounced in high aluminum composition x layer (0 <x <1), by forming a plurality of _{Al x Ga 1-x N (} 0 <x <1) layer, It is possible to more flexibly design characteristics of the entire group III nitride-based compound semiconductor device, in particular, design a light emitting layer (composition of Al _x Ga _y In _1-xy N).

The thickness of the layer consisting of Ga _y In _1-y N (0 <y <1) is
When the thickness is 15 nm or more and 30 nm or less, the function as a layer requiring a wide band gap can be maintained, and the generation of cracks can be almost completely suppressed (claim 2). At a thickness of less than 15 nm, Ga _y In _1-y N (0 <y <
The effect of reducing the elastic constant of the multilayer with Al _x Ga _1-x N (0 <x <1) layer by the layer consisting of 1) is not sufficient. Function will be reduced. Such an element is useful as a light emitting element such as a laser diode and a light emitting diode (claim 3).

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific embodiments. Note that the present invention is not limited to the following examples.

FIG. 1 shows the structure of a light emitting diode (LED) 100 according to a first embodiment of the present invention. The light emitting diode (LED) 100 has a sapphire substrate 101, and the sapphire substrate 101
An AlN buffer layer 102 having a thickness of 50 nm is formed thereon.

On the buffer layer 102, a film thickness of about 4.0 μm, a silicon (Si) concentration of 5 × 10 ¹⁸ / cm ³ ,
An n-layer 103 made of (Si) -doped GaN is formed.
On the n-layer 103, an n-cladding layer 104 having a multilayer structure with a total thickness of about 1.4 μm is formed. n clad layer 1
04 is a silicon (Si) concentration of 5 × 10 ¹⁸ / cm ³ , 20 layers of 50 nm thick silicon (Si) doped Al _0.2 Ga _0.8 N layer, silicon (Si)
Silicon (Si) -doped Ga with a concentration of 5 × 10 ¹⁸ / cm ³ and a film thickness of 20 nm
_It consists of 19 layers of _0.99 In _0.01 N layers alternately stacked.

On the n-cladding layer 104 having a multilayer structure, a well layer of Ga _0.98 In _0.02 N having a thickness of about 3 nm and a barrier layer of Al _0.05 Ga _0.95 N having a thickness of about 5 nm are alternately laminated. The light emitting layer 105 having a multiple quantum well structure (MQW) is formed. There are four well layers and three barrier layers. On the light emitting layer 105 having a multiple quantum well structure (MQW), the total film thickness is about
A p-cladding layer 106 having a multilayer structure of 1.4 μm is formed. The p-cladding layer 106 has a magnesium (Mg) concentration of 7 × 10 ¹⁹ / cm ³ and a magnesium (Mg) -doped Al having a thickness of 50 nm.
20 layers of _0.2 Ga _0.8 N layer, magnesium (Mg) concentration 7 × 10 ¹⁹ / c
m ³ , 20 nm thick magnesium (Mg) doped Ga _0.99 In _0.01 N
19 layers were alternately laminated. On the p-cladding layer 106 having a multilayer structure, a film thickness of 200 nm, a magnesium (Mg) concentration of 1 × 10 ²⁰ / cm ³ , and magnesium (Mg) -doped GaN
Is formed. Then, a Ni electrode 108A is formed on the p-contact layer 107. An electrode 108 made of Al is formed on the n-layer 103.
B is formed.

Next, a method for manufacturing a light emitting diode having this structure will be described.
The method will be described. The light emitting element 100 is made of an organic metal
Gas phase by compound vapor phase epitaxy (hereinafter referred to as “MOVPE”)
Manufactured by growth. The gas used was NH_ThreeAnd the cap
Rear gas H_TwoOr N_TwoAnd trimethylgallium (Ga (CH_Three)_Three,
Below, "TMG") and trimethylaluminum (Al (C
H_Three) _Three, Hereinafter referred to as “TMA”) and trimethylindium (In
(CH_Three)_Three, Hereinafter referred to as “TMI”) and silane (SiH_Four) And cyclo
Pentadienyl magnesium (Mg (C_FiveH_Five)_Two, Below "CP_TwoM
g ").

First, organic cleaning and heat treatment were performed.
MOVPE mounting single crystal sapphire substrate 1 with a-plane as main surface
To the susceptor placed in the reaction chamber. Next, always
H by pressure _TwoFlow through the reaction chamber at a flow rate of 10 L / min for about 30 minutes.
The sapphire substrate 101 was baked at 100 ° C.

Next, by lowering the temperature to 400 ° C., the H ₂ 1
By supplying 0 L / min, NH ₃ at 10 L / min, and TMA at 20 μmol / min for about 90 seconds, the AlN buffer layer 102 was formed to a thickness of about 50 nm. Next, the temperature of the sapphire substrate 101 was maintained at 1150 ° C., H ₂ was 10 L / min, NH ₃ was 10 L / min, TMG was 200 μmol / min,
₂₀ nmol / silane (SiH ₄ ) diluted to 0.86 ppm with H ₂ gas
min, film thickness about 4.0μm, silicon (Si) concentration 5 × 10 ¹⁸
An n-layer 103 of / cm ³ and silicon (Si) -doped GaN was formed.

After forming the above-mentioned n-layer 103, N ₂ or
H ₂ , NH ₃ , TMA, TMG and silane (SiH ₄ ) were supplied to form an Al _0.2 Ga _0.8 N layer having a thickness of about 50 nm. Then N ₂
Or supplying H ₂ , NH ₃ , TMG, TMI and silane (SiH ₄ )
A layer made of Ga _0.99 In _0.01 N having a thickness of about 20 nm was formed. 20 layers and 19 layers were laminated under the same conditions, and the total film thickness was about 1.4.
An n-cladding layer 104 having a multilayer structure of μm was formed.

Next, N_TwoOr H_Two, NH_ThreeSupply TMG, membrane
Ga about 3 nm thick_0.98In_0.02A well layer made of N was formed. Next
And N_TwoOr H_Two, NH_Three, TMG and TMA to supply a film thickness of about 5 nm
Al _0.05Ga_0.95A barrier layer made of N was formed. Further
Then, a well layer and a barrier layer are formed under the same conditions.
Ga about 3 nm thick_0.98In_0.02A well layer made of N was formed. This
MQW structure composed of four well layers and three barrier layers
A light emitting layer 105 was formed.

Next, N ₂ or H ₂ , NH ₃ , TMA, TMG and CP ₂ Mg
By supplying, to form a layer consisting of a film thickness of about 50nm Al _0.2 Ga _{0 .8} N. Next, N ₂ or H ₂ , NH ₃ , TMG, TMI and CP ₂ Mg were supplied to form a layer of Ga _0.99 In _0.01 N having a thickness of about 20 nm. Under the same conditions, 20 layers and 19 layers were laminated, respectively, to form a p-cladding layer 106 having a multilayer structure with a total film thickness of about 1.4 μm.

Next, the temperature is maintained at 1100 ° C. and N ₂ or H ₂ is added.
10 L / min, NH ₃ 10 L / min, TMG 50 μmol / min, Cp ₂ Mg 0.
Introduced at 15 μmol / min, magnesium (Mg) is 1 × 10 ²⁰ / c
m ³ doped magnesium having a thickness of about 200 nm (Mg)
A p-contact layer 107 made of doped GaN was formed.

Next, the p-contact layer 107 and the p-cladding layer 106 were uniformly irradiated with an electron beam by using an electron beam irradiation apparatus, whereby a low-resistance multi-layer wafer could be formed.

Next, by sputtering to form an SiO ₂ layer, a photoresist is applied thereon SiO _2, it was carried out photolithography. Next, the photoresist where the electrode was formed on the n-layer 103 was removed, and the SiO ₂ layer not covered with the photoresist was removed with a hydrofluoric acid-based etchant.

Next, the photoresist and the p-contact layer 107 of the portion not covered by the SiO ₂ layer, p-cladding layer 106, the active layer 105, n cladding layer 104 and n
A part of the layer 103 is vacuumed at 0.04 Torr and high frequency power is 0.44 W / cm
^2. Dry etching was performed by supplying Cl ₂ gas at a rate of 10 ml / min, followed by dry etching with Ar. In this step, n
A region for extracting an electrode from the layer 103 was formed.

Next, an electrode 108A was formed on the p-contact layer 107 by depositing nickel (Ni). On the other hand, aluminum (Al) is deposited on the
08B was formed.

The light emitting diode 1 thus obtained
In No. 00, the generation of cracks was suppressed, and a light-emitting diode with a higher output was obtained as compared with a conventional light-emitting diode having a single clad layer.

[Second Embodiment] FIG. 2 is a sectional view showing the structure of a laser diode 200 according to a specific embodiment of the present invention. The laser diode 200 has a sapphire substrate 201, and an AlN buffer layer 202 having a thickness of 50 nm is formed on the sapphire substrate 201.

On the buffer layer 202, a film thickness of about 4.0 μm, a silicon (Si) concentration of 5 × 10 ¹⁸ / cm ³ ,
An n-layer 203 made of (Si) -doped GaN is formed.
On the n-layer 203, an n-cladding layer 204 having a multilayer structure with a total film thickness of about 1.4 μm is formed. n clad layer 2
04 is a silicon (Si) concentration of 5 × 10 ¹⁸ / cm ³ , 20 layers of 50 nm thick silicon (Si) doped Al _0.2 Ga _0.8 N layer, silicon (Si)
Silicon (Si) -doped Ga with a concentration of 5 × 10 ¹⁸ / cm ³ and a film thickness of 20 nm
_It consists of 19 layers of _0.99 In _0.01 N layers alternately stacked.

On the n-cladding layer 204 having a multilayer structure, an n-guide layer 2 having a multilayer structure having a total thickness of about 120 nm is formed.
05 is formed. The n guide layer 205 is made of silicon
(Si) concentration of 1 × 10 ¹⁸ / cm ³ , 50 nm thick silicon (Si) doped A
l _0.1 Ga _0.9 between the N layer 2 layer, a silicon (Si) concentration of 1 × 10 ¹⁸ / cm
^3. A silicon (Si) -doped Ga _0.99 In _0.01 N layer having a thickness of 20 nm is inserted.

A well layer made of Ga _0.98 In _0.02 N having a thickness of about 3 nm and a well layer having a thickness of about
An active layer 206 having a multiple quantum well structure (MQW) in which barrier layers made of Al _0.05 Ga _0.95 N of 5 nm are alternately stacked is formed. There are four well layers and three barrier layers. On the active layer 206 having a multiple quantum well structure (MQW), a total film thickness of about 120
A p guide layer 207 having a multilayer structure of nm is formed. p
The guide layer 207 has a magnesium (Mg) concentration of 7 × 10 ¹⁹ / c
m ^3, while the thickness 50nm of magnesium (Mg) doped Al _0.1 Ga _{0. 9} N layer two layers, magnesium (Mg) concentration of 7 × 10 ¹⁹ / cm ^3, thickness 2
This is one in which a 0 nm magnesium (Mg) -doped Ga _0.99 In _0.01 N layer is inserted.

On the p-guide layer 207 having a multilayer structure, a p-cladding layer 2 having a multilayer thickness of about 1.4 μm is formed.
08 is formed. The p-cladding layer 208 has a magnesium (Mg) concentration of 7 × 10 ¹⁹ / cm ³ and a thickness of 50 nm.
(Mg) Doped Al _0.2 Ga _0.8 N layer 20 layers, magnesium (Mg) concentration 7 × 10 ¹⁹ / cm ³ , 20 nm thick magnesium (Mg) doped Ga _0
It consists of 19 layers of _.99 In _0.01 N layers alternately stacked. On the p-cladding layer 208 having a multilayer structure,
m, magnesium (Mg) concentration 1 × 10 ²⁰ / cm ³ , magnesium (M
g) A p-contact layer 209 made of doped GaN is formed. Then, the Ni electrode 21 is formed on the p-contact layer 209.
0A is formed. On the n layer 3, an electrode 210B made of Al is formed.

Next, a method of manufacturing a light emitting device (semiconductor laser) having this structure will be described. Light emitting element 200
Was produced by vapor phase epitaxy by metalorganic compound vapor phase epitaxy (hereinafter referred to as “MOVPE”).

First, a single crystal sapphire substrate 201 was MOVP
E Attach to a susceptor placed in the reaction chamber of the device. Next, the sapphire substrate 201 was baked at a temperature of 1100 ° C. while flowing H ₂ at normal pressure at a flow rate of 10 L / min for about 30 minutes.

Next, by lowering the temperature to 400 ° C., the H ₂ 1
By supplying 0 L / min, NH ₃ at 10 L / min, and TMA at 20 μmol / min for about 90 seconds, the AlN buffer layer 202 was formed to a thickness of about 50 nm. Next, the temperature of the sapphire substrate 201 was maintained at 1150 ° C., H ₂ was 10 L / min, NH ₃ was 10 L / min, TMG was 200 μmol / min,
₂₀ nmol / silane (SiH ₄ ) diluted to 0.86 ppm with H ₂ gas
min, film thickness about 4.0μm, silicon (Si) concentration 5 × 10 ¹⁸
An n-layer 203 of / cm ³ and silicon (Si) -doped GaN was formed.

After forming the above-mentioned n layer 203, N ₂ or
H ₂ , NH ₃ , TMA, TMG and silane (SiH ₄ ) were supplied to form an Al _0.2 Ga _0.8 N layer having a thickness of about 50 nm. Then N ₂
Or supplying H ₂ , NH ₃ , TMG, TMI and silane (SiH ₄ )
A layer made of Ga _0.99 In _0.01 N having a thickness of about 20 nm was formed. 20 layers and 19 layers were laminated under the same conditions, and the total film thickness was about 1.4.
An n-cladding layer 204 having a multilayer structure of μm was formed.

Next, N ₂ or H ₂ , NH ₃ , TMA, TMG and silane
(SiH ₄₎ by supplying, to form a layer consisting of a film thickness of about 50nm Al _{0 .1} Ga _0.9 N. Next, N ₂ or H ₂ , NH ₃ , TMG, TMI and silane (SiH ₄ ) were supplied to form a Ga _0.99 In _0.01 N layer having a thickness of about 20 nm. Further, a layer made of Al _0.1 Ga _0.9 N having a thickness of about 50 nm was formed, and an n-guide layer 205 having a multilayer structure with a total thickness of about 120 nm was formed.

Next, N ₂ or H ₂ , NH ₃ , TMG, and TMI were supplied to form a well layer of Ga _0.98 In _0.02 N having a thickness of about 3 nm. Next, N ₂ or H ₂ , NH ₃ , TMG, and TMA were supplied to form a barrier layer made of Al _0.05 Ga _0.95 N with a thickness of about 5 nm. Further, a well layer and a barrier layer were formed under the same conditions, and finally a well layer of Ga _0.98 In _0.02 N having a thickness of about 3 nm was formed.
In this way, the MQ composed of four well layers and three barrier layers
An active layer 206 having a W structure was formed.

Next, N_TwoOr H_Two, NH_Three, TMA, TMG and CP_TwoMg
Supply Al with a film thickness of about 50 nm_0.1Ga_0.9Form a layer consisting of N
did. Then N_TwoOr H_Two, NH_Three, TMG, TMI and CP_TwoSupply Mg
And a Ga film with a thickness of about 20 nm_0.99In_0.01Form a layer of N
Was. Al with a thickness of about 50 nm_0.1Ga _0.9Form a layer consisting of N
To form a multi-layered p-guide layer 207 having a total thickness of about 120 nm.
Done. Then N_TwoOr H_Two, NH_Three, TMA, TMG and CP_TwoProvide Mg
Al with a thickness of about 50 nm_{0. Two}Ga_0.8Form a layer of N
Was. Then N_TwoOr H_Two, NH_Three, TMG, TMI and CP_TwoSupply Mg
About 20nm thick Ga_0.99In_0.01Form a layer of N
Was. 20 layers and 19 layers are laminated under the same conditions, and the total film thickness is
A p-cladding layer 208 having a multilayer structure of about 1.4 μm was formed.

Next, the temperature was maintained at 1100 ° C. and N ₂ or H ₂ was added.
10 L / min, NH ₃ 10 L / min, TMG 50 μmol / min, Cp ₂ Mg 0.
Introduced at 15 μmol / min, magnesium (Mg) doped, magnesium (Mg) doped GaN with a thickness of about 200 nm
Was formed.

Next, the p-contact layer 209, the p-cladding layer 208 and the p-guide layer 20 are
7 was uniformly irradiated with an electron beam, and a low-resistance multi-layer wafer could be formed.

Next, by sputtering to form an SiO ₂ layer, a photoresist is applied thereon SiO _2, it was carried out photolithography. Next, the photoresist on the electrode formation site for the n-layer 203 was removed, and the SiO ₂ layer not covered with the photoresist was removed with a hydrofluoric acid-based etchant.

Next, the p-contact layer 209, the p-cladding layer 208, the p-guide layer 207, the active layer 206, the n-guide layer 205, the n-cladding layer 204, and the n-layer which are not covered by the photoresist and the SiO ₂ layer. Part of 203 was vacuum 0.04 Torr, high frequency power 0.44 W / cm ² , Cl ₂ gas was 10
Dry etching was performed by supplying at a rate of ml / min, and then dry etching was performed with Ar. In this step, a region for extracting an electrode from the n-layer 203 was formed.

Next, an electrode 210 A was formed on the p-contact layer 209 by depositing nickel (Ni). On the other hand, aluminum (Al) is deposited on the
10B was formed.

Next, dry etching was performed to form an end face of the resonator. Thereafter, scribe grooves were formed by scribing, and die-sinking was performed in the x-axis direction parallel to the end face of the resonator to obtain strips. The laser diode 200 thus obtained has a driving current of 50 mA and an emission output of 10 m.
W, the oscillation peak wavelength was 410 nm. In the laser diode 200, generation of cracks was suppressed, and a higher-output laser diode was obtained as compared with a conventional single-layer laser having a clad layer and a guide layer.

In the above embodiment, the metal organic chemical vapor deposition (MOCV
Although the light emitting element was manufactured by D), as a method of forming the semiconductor layer, a molecular beam vapor deposition (MBE), a halide vapor deposition (Halide VPE), or the like may be used.

In the above embodiment, a laser diode having a light emitting layer of MQW is taken as an example, but the structure of the light emitting element is not limited to this. As the structure of the light emitting element, a homo structure,
Heterostructures and double heterostructures are conceivable. These can be formed by a pin junction, a pn junction, or the like. The light emitting layer may have a single quantum well structure (SQW).

As a substrate on which a group III nitride compound semiconductor is formed, in addition to sapphire, silicon (Si), silicon carbide (SiC), spinel (MgAl ₂ O ₄ ), ZnO, MgO, or gallium nitride (GaN) Other group III nitride compound semiconductors and the like can be used. A buffer layer was formed to correct the lattice mismatch with the sapphire substrate in order to form a group III nitride compound semiconductor with good crystallinity on the sapphire substrate.However, if another substrate is used, a buffer layer must be provided. It is desirable. As the buffer layer, a group III nitride-based compound semiconductor Al _x Ga _y In _1-xy N (0 ≦
x ≦ 1, 0 ≦ y ≦ 1,0 ≦ x + y ≦ 1), more preferably Al _x Ga _1-x N
(0 ≦ x ≦ 1) is used.

Part of the composition of the group III element of the group III nitride compound semiconductor can be replaced by boron (B) or thallium (Tl), and part of the composition of nitrogen (N) can be replaced by phosphorus (P). The present invention can be substantially applied even if it is replaced with arsenic (As), antimony (Sb) or bismuth (Bi). When a light-emitting element is used, it is preferable to use a binary or ternary group III nitride-based compound semiconductor.

In the above embodiment, the cladding layer 104 or 106 or 204 or 208, the guide layer 2
The composition ratio of the group III nitride-based compound semiconductor in each unit layer of the multilayer structure of No. 05 or 207, the well layer and the barrier layer of the light emitting layer of the MQW structure is an example, and any general formula of Al _x Ga _y In _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1) may be used. In that case, the aluminum composition x, the gallium composition y, and the indium composition 1-xy may be different in each layer.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a structure of a light emitting diode 100 according to a specific embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a laser diode 200 according to a specific example of the present invention.

FIG. 3 is a cross-sectional view illustrating a structure of a conventional light emitting diode 900.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 light emitting diode 101, 201 sapphire substrate 102, 202 buffer layer 103, 203 n layer 104, 204 multi-layer n cladding layer 105, 206 MQW structure light emitting layer 106, 208 multilayer structure p cladding layer 107, 209 p contact layer 108 A 108B, 210A, 210B Metal electrode 200 Laser diode 205 Multi-layered n guide layer 207 Multi-layered p guide layer

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F041 AA40 CA05 CA34 CA40 CA46 CA49 CA57 CA65 CA74 CA83 5F073 AA74 CA07 CB05 CB07 DA05 DA24 DA31 EA07 EA24 EA29

Claims (3)

[Claims] 1. A group III nitride compound semiconductor device comprising three layers of Al _x Ga _1-x N (0 <x <1) and Ga _y In _1-y N (0 <y <1). A group III nitride compound semiconductor device having the above. 2. The group III nitride compound according to claim 1, wherein the thickness of the layer made of Ga _y In _1-y N (0 <y <1) is 15 nm or more and 30 nm or less. Semiconductor element. 3. A group III nitride compound semiconductor light emitting device, wherein the group III nitride compound semiconductor device according to claim 1 is a light emitting device.